Re: NNG Stack talk and something different

Greg,

Not only is it a matter of cost, but an issue of complexity and minimum required crew. Complexity and can be overcome with cost - to some degree - but that cost is high, especially if you want anything done in a timely manner. AT6/SNJs have a single 9-cylinder Pratt R-1340. It's a simple, supercharged engine. B-29s have four 18-cylinder Wright 3350s, which are complex turbosupercharged engines. So while you quadrupled the engines, the complexity went up by more than a factor of 8 - it's a nonlinear relationship. Plus, a B-29 requires a trained crew of 3 and probably benefits from a 3-5 man ground crew. I know a guy who does his weekly commute in an SNJ, and know another guy who commutes daily in a Stearman. They are both silly, but demonstrate one-man operation.

The knowledge, parts, and infrastructure to maintain complex radial engines are slowly going away. Airframes can be revived. So can flight controls and plumbing. Riveted aluminum structures and cable flight controls are still a constant in the airplane world. Systems devices are tougher.

Look at the folks restoring Contellations. Plenty of money, yet parts and knowledge still limit the speed at which work can be accomplished. Flight engineers with type experience are tough to find.

You can throw a lot of money at a big old airplane and still not have it fly.